MIAMI — It is a phrase that has become tired, trite and numbingly worn out with the Miami Heat.

It's also one that apparently will resonate when it comes to newly signed free-agent center Greg Oden: It's a process.

No sooner did the Heat on Wednesday formally announce the signing of the oft-injured hulking 7-foot center than Heat President Pat Riley made clear that when it comes to the No. 1 overall pick of the 2007 NBA Draft it's ... going to be a process.

"It's a great challenge for him," Riley said in a statement. "We know all about his past injuries, but we feel that there is a huge upside and the possibility of him helping us. We will continue his program and then we will tackle basketball issues after that."

Oden, 25, has not appeared in an NBA game since Dec. 5, 2009, undergoing three microfracture surgeries on his knees, while also dealing with a variety of other ailments and issues.

Unlike with other recent offseason acquisitions, even lower-level additions such as Rashard Lewis, the Heat bypassed an introductory media session, instead issuing statements Wednesday from Oden and Riley.

Oden, who passed his physical earlier in the week and flew out of South Florida on Wednesday afternoon, said, "I am very excited and happy to be here. I'm thankful to the Miami Heat organization for bringing me in and I'm ready to get to work."

Oden was waived in March 2012 by the Portland Trail Blazers, the team that drafted him one spot ahead of Oklahoma City Thunder forward Kevin Durant in 2007. Riley has been in pursuit since, hosting Oden during the Heat's championship-winning effort in the 2013 NBA Finals against the San Antonio Spurs.

"After many months of discussion, evaluations and speaking with Greg," Riley said, "we felt it was the perfect time for him to make his comeback and re-enter the NBA with the Miami Heat."

Oden, who agreed to terms last Friday, signed a two-year, $2.1 million contract that pays the veteran minimum of $1 million this season, with a player option for 2014-15.

Based on Oden's injury history, the question is not as much whether he will be available on opening night Oct. 29 against the visiting Chicago Bulls at AmericanAirlines Arena, but rather whether he will make it back in time for the Heat's lone visit of the 2013-14 season to Portland on Dec. 28, with Oden having spent all three of his previous seasons with the Trail Blazers.

Before the Heat formally announced the signing, Heat owner Micky Arison posted on Twitter, "Congrats Greg — the journey continues. Welcome to the MiamiHeat family!"